The societies are traditionally categorized by their stance towards academic fencing. There are four categories, pflichtschlagend (fencing bouts are obligatory), fakultativ schlagend (training sessions in fencing are obligatory, but not participation in actual fencing bouts), frei schlagend (both fencing practice and duels are allowed but not required of members) and nichtschlagend (no fencing). Those Swiss societies which practice fencing are united in the Schweizerischer Waffenring. Some examples of "pflichtschlagenden Studentenverbindungen" in Switzerland today are AT Alemannia (Basel), AT Utonia (Zürich) or AT Rhenania (Bern). Schweizerische Studentenverbindung Helvetia is unique in that its German-speaking sections practice fencing while its French-speaking ones do not. The Schweizerischer Studentenverein decided during the second half of the 19th century to forbid fencing to its members due to reasons of religion. Duelling was and still is seen as contrary to Christian/catholic values on which this Federation is based.